Throw out damaged or outdated test strips. Store strips in their sealed container; keep them away from heat, moisture and humidity. Be sure the strips are meant for your specific glucose meter.
Keep your glucose meter and test strips at room temperature.
Alcohol, dirt or other substances on your skin
Wash and dry your hands and the testing site thoroughly before pricking your skin.
Some meters must be coded to each container of test strips. Be sure the code number in the device matches the code number on the test strip container.
Fully insert the test strip into the monitor. Replace the monitor batteries as needed.
Not enough blood applied to the test strip
Touch a generous drop of blood to the test strip. Don’t add more blood to the test strip after the first drop is applied.
Testing site location
If you’re using a site other than your fingertip and you think the reading is wrong, test again using blood from a fingertip. Blood samples from alternate sites aren’t as accurate as fingertip samples when your blood sugar level is rising or falling quickly.
The amount of red blood cells in your blood
If you are dehydrated or your red blood cell count is low (anemia), your test results may be less accurate.